.040 bore block...

[janeto72]

Hey gang,

does anyone know what the displacement of a .040 block is vs. stock bore???
As well, when using vortec heads with such a block ....is there a specific heat range you need to have for spark plugs?? Or is there a specific heat range spark plug ,that you can only use with a vortec head no matter what engine the head is on???
thanks,
john

 

[jwaller]

Re: .040 bore block...

40 over and stock stroke is 267.66 heads dont determine displacement but they will raise the CR.

 

[janeto72]

Re: .040 bore block...

John,
If compression ratio goes up.....is this good or bad???Benefits if any??
thanks,
john

 

[canadian]

Re: .040 bore block...

Typically bad on a turbo motor. Higher compression + boost = need to run higher octane or meth injection. If it's barely noticable, you probably won't have a problem with it. There are a billion ways to deal with higher compression on a turbo motor, but that typically comes into play when you raise it by points, not tenths of a point.

Your machine shop should be able to calculate compression ratio based on combustion chamber volume, piston, rod, and stroke of your combination. Chances are with an off the shelf turbo piston you're safe.

 

[jwaller]

Re: .040 bore block...

it's not a big enough change to matter, besides the pistons typically used (trw and SRP) lower the ratio anyway so vortecs just get you back to where you started.

 

[janeto72]

Re: .040 bore block...

So with the use of vortecs ,.040 turbo pistons , your ...safe .
thanks,guys
john